1. Field of the Invention
The present invention relates to chip antennas and particularly a chip antenna used for mobile communication and local area networks (LAN).
2. Description of the Related Art
Conventional antennas include monopole antennas and chip antennas, for example.
FIG. 9 shows a typical prior art monopole antenna 1. The monopole antenna 1 has a conductor 2 perpendicular to an earth plate (not shown in the figure) in air (dielectric constant .epsilon.=1 and relative permeability .mu.=1), the one end 3 of the conductor 2 forming a feeding section and the other end 4 being a free end.
FIG. 10 is a side view of a typical prior art chip antenna 5. The chip antenna 5 comprises an insulator 6, a coil conductor 7, a magnetic member 8, and external connecting terminals 9a and 9b.
Each of the prior art monopole antenna and chip antenna set forth above has only one feeding section and conductor, and thus has only one resonance frequency. Thus, a plurality of monopole antennas or chip antennas are required for responding to two or more different resonance frequencies, and they are not applicable to uses, requiring compact antennas, such as mobile communication, for the reason of their sizes.